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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

59 results found.

  1. GRB 250421B: AstroSat CZTI detection of a bright long burst
  2. LIGO/Virgo/KAGRA S250211aa: Updated Sky localization and EM Bright Classification
  3. Fermi trigger No 758442826: Global MASTER-Net observations report
  4. GRB 250101A: BOOTES-4/MET optical afterglow detection
  5. GRB 240809A: Swift/UVOT Detection
  6. Fermi GRB 240727A: Global MASTER-Net observations report
  7. GRB 240627A: AstroSat CZTI detection
  8. Konus-Wind detection of GRB 240607A
  9. EXO 0748-676: Swift-BAT refined analysis
  10. Trigger 1236151: Swift detection of EXO 0748-676
  11. Fermi GRB 240605A: Global MASTER-Net observations report
  12. GRB 240531A: AstroSat CZTI detection of a short burst
  13. GRB 240426A: AstroSat CZTI detection
  14. Fermi trigger No 709083929: Global MASTER-Net observations report
  15. GRB 230524B: AstroSat CZTI detection
  16. GRB 230427A: Swift/UVOT Detection
  17. GRB 221024A: Swift-XRT refined Analysis
  18. GRB 220702B: AstroSat CZTI detection
  19. GRB 220317A: Fermi GBM detection
  20. GRB 210330A: AstroSat CZTI detection
  21. Swift GRB 210318A: Global MASTER-Net observations report
  22. Fermi trigger No 636187116: Global MASTER-Net observations report
  23. GRB 210126A: AstroSat CZTI detection
  24. Fermi trigger No 630389391: Global MASTER-Net observations report
  25. Fermi trigger No 605756501: Global MASTER-Net observations report
  26. Fermi trigger No 600666048: Global MASTER-Net observations report
  27. Fermi trigger No 600448273: Global MASTER-Net observations report
  28. IceCube Alert 191215.47: Global MASTER-Net observations report
  29. LIGO/Virgo S190910d Global MASTER-Net observations report
  30. Konus-Wind observation of GRB 190206A
  31. GRB 161219B: POLAR Observation
  32. GRB 161108A: Swift/UVOT Upper Limits
  33. GRB 160408A: Swift/UVOT Upper Limits
  34. GRB 150627A: Swift/UVOT Detection
  35. GRB 150626A: Swift/UVOT Upper Limits
  36. Swift triggered on a source in Terzan 5 (trigger=637212)
  37. GRB 141130A: Mondy optical observations
  38. Konus-Wind observation of GRB 140906C
  39. SGR 1745-29 (Swift trigger 565443), Swift-BAT refined analysis
  40. GRB 110825A: Suzaku WAM observation of the prompt emission
  41. GRB 110205A: Suzaku WAM observation of the prompt emission
  42. GRB 101008A: Swift-BAT refined analysis
  43. GRB 101008A: Enhanced Swift-XRT position
  44. Konus-Wind observations of GRB 091010
  45. GRB090926B: Swift/UVOT Upper Limits
  46. GRB 090407: Swift UVOT Upper Limits
  47. Konus-Wind observation of GRB 081121
  48. Swift detection of AX J1749.1-2639
  49. Swift/UVOT observations of GRB080130
  50. Further Retractions of previous Swift-BAT triggers
  51. Retractions of previous Swift-BAT triggers
  52. GRB 060813: A long, bright GRB detected with Suzaku WAM
  53. GRB 060515: Super-LOTIS Observations
  54. GRB 050525, spectral lag pseudo-redshift
  55. GRB 050128: Swift XRT prompt afterglow position
  56. IPN confirmation of the reactivation of SGR1900+14
  57. GRB 990123: Reduced HST Images
  58. GRB 990123: Updated Keck Spectroscopy Results
  59. GRB980329 VLA observations

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